(1) Reference to Applicant's Related Patents
Patents U.S. Pat. Nos. 5,379,603 and 5,555,734 of which this applicant is a co-inventor describe a preferred heat exchanger for use with this invention.
(2) Field of the Invention
This invention relates to improvements to existing ice making and beverage dispensing machines that can be easily installed on location to extract the cooling energies embodied within the cold waste waters which are conventionally ejected to the sewer by both machines.
(3) Description of the Prior Art
Beverage dispensers and ice making machines are widely used worldwide especially in warm and hot climates. This invention is not limited to any particular type machine, or combinations thereof. This invention relates not to the machines per se but to novel improvements to existing ice making and beverage dispensing machines. These improvements can be easily installed on location, fixedly or movably, at a convenient out of the way site adjacent to but outside of the machines, so as to preserve precious space allocated to and occupied by the ice storage bin of the beverage dispenser machine.
Efforts to extract the cooling energy embodied within the waste water from a single machine, but not from both machines simultaneously, are described in the patent literature. Such efforts however have not been successful in the market place, except for a water prechiller, known in the trade as MAXIMICER.RTM. (a registered trademark of applicant's assignee), for use with ice machines and described in said U.S. Pat. Nos. 5,379,603 and 5,555,734.
It is a primary object of the present invention to extract the cooling energies that are embodied within the cold waste waters conventionally ejected to the sewer when both machines commonly operate in tandem, i.e., the ice machine directly supplies the cooling ice and the food ice to the ice bin of the beverage dispenser. These extracted cooling energies can be simultaneously used to prechill the ambient tap water flowing into the ice machine to make the cooling ice and the food ice for the ice bin of the beverage dispenser machine, and/or to prechill the same ambient tap water used by the beverage dispenser machine in its process of dispensing different kinds of cold beverages at about 40.degree. F. and below. The cooling ice in the ice bin is used by the cold plate of the beverage dispenser machine to cool the different kinds of syrups as well as the tap water all passing through the cold plate in heat exchange relationship with the cooling ice, i.e., the cooling ice is used as the non-mechanical source of cooling energy. On the other hand, the food ice is made available to the public for consumption as in a fast-food restaurant.
A soda drink "goes flat" as the temperature of a particular beverage from the dispenser's cold plate rises because the amount of gas the soda drink can hold decreases as its temperature increases. For the purpose of carbonation, it is desired that the temperature of the dispensed beverage be maintained at about 40.degree. F. or below, which is a very difficult and critical task to accomplish, especially in the hot summer months.
The apparatus and method of this invention are especially useful in fast-food restaurants when the output of the ice maker machine is acutely insufficient to meet the demand by the beverage dispenser for cooling ice and consumption food ice. This demand can only be partially accommodated by using a larger ice machine which uses more energy because ice machines are not designed for rapid recovery. The ice maker machine recovery time is the time required by an ice maker machine to regain a substantially full ice bin after the ice has been removed from the bin.
Naturally, efforts have been made to render the beverage delivery process more energy efficient as will become apparent from the following patents. Such efforts have been largely unsuccessful. These exemplary patents will set the stage for the problems involved to which this invention brings a novel solution.
U.S. Pat. No. 5,226,296, issued Jul. 13, 1993, describes a typical cold plate for cooling different beverages drawn from beverage supply cylinders. The cold plate has a run-off roof, defined by a sloping end, and side sections. The cold plate is received in the well of a thermally-insulated sink, chest or bin having an open bottom bordered by a ledge. The base of the cold plate is seated on the ledge in spaced relation to the sides of the well to define a gutter having a water drain.
Embedded in the cold plate are cooling coils terminating in input and output terminals that project from the underside of the base. The coils' inputs are coupled by upstream lines to respective beverage supply cylinders. The coils' outputs are coupled by downstream lines to a soda valve dispenser to selectively dispense desired cold soda beverages. The thermally-insulated sink is filled with ice cubes covering and being in heat-exchange relationship with the exposed surfaces of the cold plate and with the cooling coils embedded therein to cool the beverages flowing therethrough.
In this manner, heat energy becomes transferred from the warm beverages flowing through the coils to the ice cubes, causing their melt down and a run off of the ice-water mixture from the sloped roof through the gutter and into an exterior drain.
U.S. Pat. No. 5,549,219 describes an apparatus for prechilling and preparing a beverage by directly contacting water and ice in a heat exchanger to cool the water and melt the ice, and to produce an outflow of about 36.degree. F. water as well as ice cold waste water from the melted ice. The outflowing cold water from the prechiller is then carbonated in a carbonator, which is also in heat exchange contact with the ice for keeping the contents of the carbonator cool. The carbonated water is manifolded to individual conduits leading to a plurality of individual soda dispensing nozzles.
U.S. Pat. No. 5,350,086 describes a beverage dispenser having a prechiller for prechilling the incoming ambient water. The prechiller uses tubing means that comprises four inter-connected linear tube segments adjacent to the side walls of the ice bin. The tubing means is embedded within an aluminum body that is locked in place adjacent to the body of the cold plate in a thermal isolating manner. Both bodies are in thermal contact with the ice in the bin of the beverage dispenser.
U.S. Pat. No. 4,798,061 describes an ambient water prechiller used in conjunction with a preexisting beverage system to cool the water input to an ice maker. An electrically driven pump circulates water through concentric tubing immersed in the ice bank of the beverage system to supply cool water to the input line to the ice maker.
U.S. Pat. No. 4,856,678 shows a beverage dispenser using an ice water precooler. The dispenser has a rectangular ice bin in the bottom of which is an aluminum cold plate having vertical apertures to permit waste water from the melting ice on the cold plate to run off into a waste water tank situated immediately underneath the ice storage bin of the beverage dispenser. A helical concentric tubing is immersed in the waste liquid tank. Ambient water is supplied to the innermost tube of the concentric tubing and thereafter to a serpentine passage through the cold plate. A pump is utilized to recirculate the waste water from the tank through a second serpentine passage in the cold plate, through the outer conduit of the concentric tubing, and back to the tank. The outflowing cold water from the prechiller is carbonated in a carbonator which is also in heat exchange contact with the ice for keeping the contents of the carbonator cool. The carbonated water is manifolded to individual conduits leading to a plurality of individual soda dispensing nozzles.
In general, such known tap water prechillers
(a) necessarily limit the maximum space that can be allocated for the beverage dispenser's ice bin, and hence the maximum volume of ice that can be stored in the bin, and
(b) tend to preclude utilizing an additional source of cooling energy, such as the cold waste water purged from the ice maker machine, due to health hazard concerns about introducing a pool of liquid waste water from the ice maker to within close proximity to the food ice stored in the ice bin of the beverage dispenser. Such use of the liquid waste water from the ice maker might possibly contaminate the food ice in the ice bin and/or the beverages from and/or passing through the dispenser machine's cold plate.
For example, the vertical drain holes proposed by said U.S. Pat. No. 4,856,678 are likely to expose the food ice in the ice bin to contamination from the liquid waste waters stored in the waste water tank positioned in close proximity to the ice bin within the space occupied by the beverage dispenser machine. Also, the space inside the concentric tubing of this patent is likely to become clogged up with minerals, and the submersed electric pump's operational life is likely to become short and its use might be dangerous.
It is a main object of this invention to selectively channel all the cold waste waters, intrinsic in existing beverage dispenser and ice maker machines, to flow into a single waste water heat exchanger that is positioned on location at a convenient out of the way site, so as to be physically separated from and outside of the space occupied by the frame structure of the beverage dispenser machine. As a direct consequence thereof the present invention
(a) does not limit the maximum space that can be allocated for the beverage dispenser's bin, and hence the maximum volume of ice that can be stored in the bin,
(b) minimizes the health hazard concerns, based on exposing the food ice in the ice bin of the beverage dispenser machine to possible contamination, because the pool of liquid waste waters from the ice maker and the liquid waste water from the beverage dispenser machines are safely stored within the thermally-isolated chamber of a heat exchanger preferably positioned and serviced outside of the frame structure of the beverage dispenser machine,
(c) can selectively utilize the additional cooling energy which is embodied within the purge cold waste water discharged during every ice-making cycle of the ice machine,
(d) can achieve the desired prechill temperatures in shorter time intervals, and thus accelerate recovery times at periods of high volume beverage and ice food usage,
(e) can reduce the melting of ice in the drink dispenser's ice bin, thus reduce energy consumption and increase both the availability of food ice and the availability of ice as the coolant source of the beverage dispenser's cold plate,
(f) can increase the ice production in the ice machine which increases both the availability of food ice and the availability of ice as the coolant source for the cold plate, and
(g) effectively reduces ice melting in the dispenser machine's bin, reduces energy and ice consumption by the dispenser machine, and substantially increases, without additional energy costs, the ice output by the ice maker machine and the volume of beverage output by the beverage dispenser.